Apple began including screen sharing nearly 20 years ago in its Mac operating system. If you have multiple Macs in your home or office on the same local area network (wired, wireless, both, or even two Macs connected via Thunderbolt), you can observe or control another Mac on that network. Some regular users aren’t aware it exists because they’ve never needed to use it.
It’s not entirely obvious how to set it up or access it as it requires changes on both the Mac to be shared and looking in the correct place on the Mac viewing the other’s screen. It can be handy to use if you have multiple Macs in different places or a Mac without a keyboard and mouse used as part of a home A/V system, or one bereft of head (display) and inputs deployed as a server.
To set this up on the Mac that can be viewed or controlled:
- Go to System Preferences > Sharing or System Settings > General > Sharing.
- Check the box or flip the switch next to Screen Sharing.
- With “All users” selected, anyone with an account on the machine can access it remotely on the local network. You can limit it, as with most other sharing services, by selecting users and groups. (In more recent versions of macOS, you can find this setting by clicking the “i” icon.)
On any other Mac:
- Go to the Finder and select the Mac’s name in the Sidebar in any Finder window. (Choose View > Show Sidebar if you don’t see the Sidebar.)
- In the upper-right corner of the window, click Share Screen.
- macOS launches the Screen Sharing app. Log in to the Mac using your credentials on the screen that appears.
The other Mac will have “Your screen is being observed” or two overlapping rectangles in the system bar to indicate remote sharing.
If you don’t see the Mac you want to view in the Sidebar, in the Finder of that computer choose Finder > Preferences and make sure you have “Bonjour computers” checked under “Show these items in the sidebar.”
This Mac 911 article is in response to a question submitted by a Macworld reader.
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